Umbrella frame

ABSTRACT

An umbrella frame has a main shaft and multiple branches pivotally attached around the main shaft. The main shaft has an immovable upper base and a movable lower base each having multiple retaining slots. Each branch is divided into a front section, a middle section and a rear section and has a supporting rib and a pulling rib both pivotally attached under the front section. The front sections and the supporting ribs have pin heads to respectively engage the retaining slots on the upper and lower bases so that the branches are pivotally attached to the main shaft. Moreover, the supporting rib, the pulling ribs, the front section and middle section perform a quaternary-linkage to make operation conveniently and stably. Additionally, the umbrella frame is made of high-stiffness plastic so that the umbrella frame does not rust and has excellent anti-deforming efficiency.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an umbrella frame, and more particularly to an umbrella frame that is made of high-stiffness plastic to substitute conventional metal rivets, modified in structure to make umbrella frame stable without deformation and enables to change different actuating modules.

2. Description of Related Art

Conventional umbrella frames are made of metal material, wherein pivotal joints on the umbrella frames are secured by copper rivets. Particularly, multiple ribs are radially attached around a main shaft by a metal wire penetrating all ribs and pivoted on the metal wire. Attaching the ribs by the metal wire is time-consuming in manufacturing procedures and the pivotal joints and the ribs are rusted, cracked or broken easily so that the umbrella frequently has malfunction problems when extends or contracts. Moreover, the umbrella frame may be deformed or bent when an umbrella canopy on the umbrella frame resists strong wind because the ribs are thin and do not have excellent stiffness.

Although manufacturing technic of the umbrella is improved to decrease the malfunction frequency, fundamental problems on structure and material are not resolved. Some improved conventional umbrella frames are made of fiber reinforced plastic (FRP) that enhances the anti-rust efficiency of the umbrella frame, however, structure design is still incomplete in efficiently improving stiffness, assembling convenience and modular change of activating devices.

To overcome the drawbacks of the conventional umbrella frame, a novel umbrella frame is provided to obviate the foregoing drawbacks.

SUMMARY OF THE INVENTION

One main objective of the present invention is to provide an umbrella frame that has pin heads individually formed on branches and support ribs and has multiple corresponding retaining slots defined in a upper base and a lower base to respectively and pivotally engage the pin heads so that the conventional metal wire is eliminated and the umbrella frame is simplified to make assemble or disassembly quick without using auxiliary machines.

Another main objective of the present invention is to provide an umbrella frame that is made of stiffness material to make the structure have high resistance for deformation and excellent durability.

Still another main objective of the present invention is to provide an umbrella frame that has various pressing devices having humanity-oriented design to make operation of the umbrella frame convenient.

Further another main objective of the present invention is to provide an umbrella frame that has plastic joints to eliminate the conventional copper rivets and to avoid rust problem.

To achieve the foregoing main objectives, the umbrella frame in the present invention comprises:

a main shaft with a retractable sheet having

a upper base secured on a top of the main shaft and having multiple retaining slots formed around the upper base to respectively engage with multiple branches;

a locking ring with a cap mounted on the upper base;

a lower base movably sleeving the main shaft and having multiple retaining slots;

multiple supporting ribs pivotally connected between the lower base and the multiple branches individually, wherein each of the multiple supporting rib has a pin head pivotally engaged a corresponding one of the multiple retaining slots on the lower base;

an actuating device attached to the lower base to enable the lower base to slide on the main shaft;

wherein, each of the multiple branches is divided into a front section, a middle section and a rear section pivotally connected in sequence;

the front section has a pivot head pivotally engaged a corresponding one of the multiple retaining slot on the upper base, a pivot hole defined at a middle portion of the front section to pivotally engage the corresponding supporting rib, and a pulling rib pivotally connected between the supporting rib and the middle section;

the middle section has a resilient strip longitudinally extended inside the middle section and connected between the front section and the rear section;

wherein, the actuating device aligns with the retractable sheet and is retained by the retractable sheet when the umbrella frame is fully extended;

wherein all joints between the branches and the upper base or the supporting ribs and the lower base are pivotal in form of the pin heads and the corresponding retaining slots to allow the branches rotating within a limited angle then the umbrella frame extends or retracts;

wherein, all elements of the umbrella frame are made of high-stiffness plastic material.

By having a structure described above, the umbrella frame can be operated conveniently, quickly and stably and has excellent deforming-resistance to make the umbrella frame durable.

Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side plan view of an umbrella frame in accordance with the present invention, wherein the umbrella frame is fully extended;

FIG. 2 is a side plan view of the umbrella frame in FIG. 1, wherein the umbrella frame is completely retracted;

FIG. 3 is an exploded perspective view of a branch in the umbrella frame;

FIG. 4 is a perspective view of the branch in FIG. 3, wherein the branch is assembled;

FIG. 5 is an exploded perspective view of a main shaft in the umbrella frame;

FIG. 6 is a perspective view of the main shaft in combination with the branch;

FIG. 7 is a cross-sectional view of the umbrella frame to show engagements between the main shaft and the branch;

FIG. 8 is cross-sectional side view of a lower base with an actuating sleeve mounted on the upper base;

FIG. 9 is a cross-sectional side view of a positioning sleeve mounted on the upper base;

FIG. 10 is an exploded perspective view of the lower base with the actuating sleeve in accordance with FIG. 8; and

FIG. 11 is an exploded perspective view of the lower base with the positioning sleeve in accordance with FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

An umbrella frame in accordance with the present invention is preferably made of high-stiffness plastic and comprises a main shaft and multiple branches pivotally attached around the main shaft. The main shaft has an upper base and a lower base each having multiple retaining slots. Each branch is divided into a front section, a middle section and a rear section and has a supporting rib and a pulling rib both pivotally attached under the front section. The front sections and the supporting ribs have pin heads to respectively engage the retaining slots on the upper and lower bases so that the branches are pivotally attached to the main shaft. Moreover, the supporting rib, the pulling ribs, the front section and middle section perform a quaternary-linkage to make operation conveniently and stably. Additionally, the umbrella frame is made of high-stiffness plastic material so that stiffness is also improved.

With reference to FIGS. 1 and 2, the umbrella frame comprises a main shaft 1, an upper base 20, an upper locking ring 21, a cap 22, multiple branches, a lower base 30, a lower locking ring 31 and an optional actuating sleeve 40A. Each branch is composed of a front section 50, a middle section 80, a rear section 10, a supporting rib 60, a pulling rib 70 and a resilient strip 90. Selectively, the actuating sleeve 40A has a resilient button 40A1. Relative positions and features of the umbrella frame in complete extension are shown in FIGS. 1 and 2.

With further reference to FIG. 5, the main shaft 1 has a top end, a bottom end and a retractable sheet 11 attached near the top end. The upper base 20 is secured on the top end of the main shaft 1 and has a top, a bottom, multiple blocks, multiple retaining slots 201, multiple dividing flanges 202, and a threaded hole 203. The multiple blocks are formed around the upper base 20 so that the multiple retaining slots 201 are evenly and longitudinally defined in intervals. Each retaining slot 201 is rectangular in cross-section and has flanges oppositely and respectively protruding from two adjacent blocks at bottom edges and front edges to keep the retaining slot 201 narrow at openings. The multiple dividing flanges 202 are formed around the upper base 20 near the top to respectively align with multiple retaining slots 201. The threaded hole 203 is longitudinally defined at a center of the upper base 20. The upper locking ring 21 is detachably mounted on the upper base 20 and has an inner edge and multiple notches 211 evenly defined in intervals at the inner edge to snugly engage the dividing flanges 202 on the upper base 20 when the upper locking ring 21 combines with the upper base 20. The cap 22 is detachably mounted on the upper locking ring 21 and has a threaded rod 221 formed under the cap 22 to screwly attach the threaded hole 203 so as to keep the upper locking ring 21 firmly locate on the upper base 20.

The lower base 30 is a runner slidably mounted on the main shaft 1 and composed of a tube with a top and a bottom, multiple blocks, multiple retaining slots 301, multiple dividing flanges 302 and a cutout 303. The multiple blocks are formed around the tube so that the multiple retaining slots 301 are evenly and longitudinally defined in intervals between the multiple blocks around the lower base 30. Each retaining slot 301 is rectangular in cross-section and has flanges oppositely and respectively protruding from two adjacent blocks at top edges and front edges to keep the retaining slot 201 narrow at openings. The multiple dividing flanges 302 are formed around the tube near the bottom to respectively align with multiple retaining slots 301. The lower locking ring 31 is detachably mounted on the lower base 30 and has an inner edge and multiple notches 311 evenly defined in intervals on the inner edge to snugly engage the dividing flanges 302 on the lower base 30 when the lower locking ring 31 is attached under the lower base 30. The cutout 303 is defined at the bottom of the lower base 30. The actuating sleeve 40A is tubular to sleeve the bottom of the lower base 30 and then to keep the lower locking ring 31 abutting to the multiple blocks on the lower base 30.

Moreover, the actuating sleeve 40A further has the resilient button 40A1 that aligns to the cutout 303 when the actuating sleeve 40 A combines with the lower base 30.

With further reference to FIG. 3, each branch is divided into a front section 50, a middle section 80 and a rear section 10 pivotally engaged one by one in sequence and has a supporting rib 60 and a pulling rib 70 both pivotally attached under the front section 50.

The front section 50 has two ends, a pivot hole 502, and a pivot bracket 503. The two ends of the front section 50 are pin heads 501, 504, wherein one of the pin heads 501 pivotally engages a corresponding one of the retaining slot 201 on the upper base 20 and the other one of the pin heads 504 engages the middle section 80. The pivot hole 502 is defined at a middle of the front section 50 and the pivot bracket 503 is formed on a top face of the front section 50 near the pin head 504 adjacent to the middle section 80.

The supporting rib 60 pivotally attaches between the lower base 30 and the front section 50 and also has two pin heads 601, 603 respectively engaged one retaining slot 301 on the lower base 30 and the pivot hole 502 on the front section 50. The supporting rib 60 further has a pivot hole 602 defined near the pin head 603 adjacent to the front section 50.

The pulling rib 70 pivotally attaches between the supporting rib 60 and the middle section 80 and also has two pin heads 701, 702 respectively engaged the pivot hole 602 on the supporting rib 60 and the middle section 80.

The middle section 80 is a hollow elongated rod with a top opening and a channel and has an adjacent end, a pin head 804, a resilient strip 90 and a H-shape barrier 803. The adjacent end and the pin head 804 respectively connected to the front section 50 and the rear section 10, wherein the adjacent end has a first pivot bracket 801 at distal to engage the corresponding pin head 702 on the pulling rib 70 and a second pivot bracket 802 near the first pivot bracket 801 to engage the corresponding pin head 504 on the front section. The H-shaped barrier 803 mounts on the middle section 80 to bridge at the top opening and to keep the resilient strip 90 being retained inside the channel of the middle section 80.

The resilient strip 90 extends along the channel of the middle section 80 and has a pivoting head 901 and a U-shaped bracket 902 respectively engaged the pivot bracket 503 on the front section 50 and the rear section 10.

The rear section 10 has a free end and a pivot head 101 formed opposite to the free end at distal to engage the U-shaped bracket 902 of the resilient strip 90 and a pivot bracket 102 formed near the U-shaped bracket 902 to engage the pin head 804 on the middle section 80.

With reference to FIG. 4 showing the umbrella frame in assembly, the front section 50, the supporting rib 60, the pulling rib 70, the middle section 80, and the rear section 10 are combined together to compose one branch in accordance with the FIG. 3. After attaching the branch to the main shaft 1, configuration of the branch and the main shaft 1 is shown in FIG. 6. Since all elements of the branch in the umbrella frame are pivotally connected to each other and to the upper and lower bases 20, 30, the branch can be retracted and extended by moving the lower base 30.

With reference to FIG. 7, the pin heads 501, 601 on the front section 50 and the supporting rib 60 respectively and pivotally attach to the upper and lower bases 20, 30. The pin head 501 on the front section 50 is received in the retaining slot 201 and limited by the upper locking ring 21 and the flanges on the adjacent blocks so that the pin head 501 stably pivots inside the retaining slot 201 without disengaging from the retaining slot 201.

Engagement of the pin head 601 on the supporting rib 60 to the lower base 30 is the same with the one on the front section 50 to the upper base 20 except the retaining slot 301 has an inner space slightly larger than the pin head 601 to allow the pin head 601 moving longitudinally when the lower base 30 slides on the main shaft 1.

Moreover, the pin head 603 of the supporting rib 60 pivotally engages the pivot hole 502 on the front section 50.

With reference to FIGS. 8 and 10 showing engagement of the actuating sleeve 40A and the lower base 30, the actuating sleeve 40A is made of resilient material and has the resilient button 40A1 formed at a middle on the actuating sleeve 40A. When the actuating sleeve 40A sleeves on the lower base 30, the resilient button 40A1 aligns to the cutout 303. The lower base 30 moves upward along the main shaft 1 with the actuating sleeve 40A until the retractable sheet 11 is pushed into the main shaft 1 by the lower base 30 and then automatically emerges again to penetrate the cutout 303 so that the retractable sheet 11 is locked by the actuating sleeve 40A to keep the umbrella frame at an fully extended position. The retractable sheet 11 can be pushed back to the main shaft 1 by pressing the resilient button 40A1 and moving the lower base 30 downward to disengage the retractable sheet 11 from the actuating sleeve 40A.

With reference to FIGS. 9 and 11, the actuating sleeve 40A is substituted by a positioning sleeve 40B. The positioning sleeve 40B has a structure similar to the one of the actuating sleeve 40A except the resilient button 40A1 so that the retractable sheet 11 is kept below the positioning sleeve 40B after the lower base 30 and the positioning sleeve 40B passing. When the retractable sheet 11 is pushed into the main shaft 1, the lower base 30 enables to move downward to close the umbrella frame.

According to above description, features of the umbrella frame in the present invention are disclosed:

1. Engagement between the front section 50 and the upper base 20 is to push the pin head 501 into the retaining slot 201 and then mount the upper locking ring 21 and the cap 22 on the upper base 20 to make the front section 50 pivot up or down within a limited angle.

2. Engagement between the supporting rib 60 and the lower base 30 is to push the pin head 601 into the retaining slot 301 and then mount the lower locking ring 31 and actuating sleeve 40A on the lower base 30 to make the supporting rib 60 pivot up or down within a limited angle.

3. The front section 50, the supporting rib 60, the pulling rib 70 and the middle section 80 are pivotally connected to perform a movable quaternary-linkage that makes the branch move stable to reduce malfunction and deformation when the umbrella frame retracts or extends.

4. The resilient strip 90 on the middle section 80 connects the front section 50 and the rear section 10 to provide a pulling force to the rear section 10 so as to keep the whole branch straight and stable when the umbrella frame fully extends.

5. Since all elements in the umbrella frame are made of high-stiffness plastic, especially at joints, rust and deformation problems are eliminated.

6. All joints between the branches and the bases 20, 30 are pivotal structures so that the conventional metal wire is avoided and assembling method of the umbrella frame is simplified without using auxiliary machines.

7. The actuating sleeve and the positioning sleeve are exchangeable to make the umbrella frame versatile in structure.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present invention of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts any be resorted to without departing from the spirit and scope of the invention. 

1. An umbrella frame comprising: a main shaft 1 with a top having a retractable sheet 11 attached near the top; an upper base 20 immovably mounted on the top of the main shaft 1 and having multiple retaining slots 201 longitudinally defined around the upper base 20; an upper locking ring 21 with a cap 22 detachably mounted on the upper base 20; a lower base 30 slidably mounted on the main shaft 1 and having multiple retaining slots 301 longitudinally defined around the lower base 30; a lower locking ring 31 detachably mounted on the lower base 30; and multiple branches radially attached to the upper base 20 and the lower base 30 around the main shaft 1; wherein each branch is divided into a front section 50, a middle section 80 and a rear section 10 pivotally connected in sequence and further comprising a supporting rib 60 and a pulling rib 70; the front section 50 has two pin heads 501, 504, wherein one of the two pin heads 501 of the front section 50 engages a corresponding one of the multiple retaining slots 201 on the upper base 20; the supporting rib 60 pivotally attaches between the lower base 30 and the front section 50 and has two pin heads 601, 603, wherein one of the two pin heads 601 of the supporting rib 60 engages a corresponding one of the multiple retaining slot 301 on the lower base 30; the pulling rib 70 pivotally attaches between the supporting rib 60 and the middle section 80; the middle section 80 has a resilient strip extending along the middle section 80 and pivotally connected between the front section 50 and the rear section
 10. 2. The umbrella frame as claimed in claim 1, wherein the umbrella frame further has an actuating sleeve 40A attached to the lower base 30; the actuating sleeve 40A sleeves on the lower base 30 below the multiple retaining slots 301 and has a resilient button 40A1 formed on the actuating sleeve 40A; the lower base 30 further has a cutout 303 defined to align to the resilient button 40A1 and operationally align to the retractable sheet 11 when the umbrella frame is fully extended.
 3. The umbrella frame as claimed in claim 1, wherein the front section 50 has a pin hole 502 defined at a middle of the front section 50 to engage the other one of the two pin heads 603 of the supporting rib 60; the supporting rib 60 has a pin hole 602 defined near the pin head 603 near the front section 50; the pulling rib 70 has two pin heads 701, 702, wherein one of the two pin heads 701 is pivotally engaged the pin hole 602 of the supporting rib 60; the middle section 80 has a pin head 804 connected to the rear section 10 and an adjacent end having a first pivot bracket 801 at distal to engage the other one of the two pin heads 702 on the pulling rib 70; and a second pivot bracket 802 near the first pivot bracket 801 to engage the other one of the two pin heads 504 on the front section
 50. 4. The umbrella frame as claimed in claim 1, wherein the umbrella frame is made of high-stiffness plastic.
 5. The umbrella frame as claimed in claim 1, wherein the upper locking ring 21 has an inner edge and multiple notches 211 defined in intervals on the inner edge; the upper base 20 has a top and multiple dividing flanges 202 formed around the upper base 20 individually over the multiple retaining slots 201 to snugly combine with the multiple notches 211 when the upper locking ring 21 mounted on the upper base
 20. 6. The umbrella frame as claimed in claim 5, wherein upper base 20 further has a threaded hole 202 defined in the top; the cap 22 mounted on the upper locking ring 21 and has a threaded rod 221 to engage the threaded hole 202 to secure the upper locking ring 21 on the upper base
 20. 7. The umbrella frame as claimed in claim 1, wherein the lower locking ring 31 has an inner edge and multiple notches 311 defined in intervals on the inner edge; the lower base 30 has a bottom and multiple dividing flanges 302 formed around the lower base 30 below the retaining slot 201 to snugly combine with the multiple notches 311 when the lower locking ring 31 mounted on the lower base
 30. 8. The umbrella frame as claimed in claim 2, wherein the lower locking ring 31 has an inner edge and multiple notches 311 defined in intervals on the inner edge; the lower base 30 has a bottom and multiple dividing flanges 302 formed around the lower base 30 below the retaining slot 201 to snugly combine with the multiple notches 311 when the lower locking ring 31 is clamped between the lower base 30 and the actuating sleeve 40A.
 9. The umbrella frame as claimed in claim 1, wherein the umbrella frame further has a positioning sleeve 40A1 attached to the lower base
 30. 